linux-kernel - Re: [PATCH v4 1/2] acpi/ghes: Process CXL Component Events

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <ZjE5O87IxxMAoaFz@agluck-desk3>
Date: Tue, 30 Apr 2024 11:32:27 -0700
From: Tony Luck <tony.luck@...el.com>
To: Ira Weiny <ira.weiny@...el.com>
Cc: Dave Jiang <dave.jiang@...el.com>,
	Dan Williams <dan.j.williams@...el.com>,
	Jonathan Cameron <jonathan.cameron@...wei.com>,
	Smita Koralahalli <Smita.KoralahalliChannabasappa@....com>,
	Shiju Jose <shiju.jose@...wei.com>,
	Dan Carpenter <dan.carpenter@...aro.org>,
	Yazen Ghannam <yazen.ghannam@....com>,
	Davidlohr Bueso <dave@...olabs.net>,
	Alison Schofield <alison.schofield@...el.com>,
	Vishal Verma <vishal.l.verma@...el.com>,
	Ard Biesheuvel <ardb@...nel.org>, linux-efi@...r.kernel.org,
	linux-kernel@...r.kernel.org, linux-cxl@...r.kernel.org,
	"Rafael J. Wysocki" <rafael@...nel.org>,
	Borislav Petkov <bp@...en8.de>
Subject: Re: [PATCH v4 1/2] acpi/ghes: Process CXL Component Events

On Fri, Apr 26, 2024 at 08:34:00PM -0700, Ira Weiny wrote:
> @@ -707,6 +805,18 @@ static bool ghes_do_proc(struct ghes *ghes,
>  		}
>  		else if (guid_equal(sec_type, &CPER_SEC_PROC_ARM)) {
>  			queued = ghes_handle_arm_hw_error(gdata, sev, sync);
> +		} else if (guid_equal(sec_type, &CPER_SEC_CXL_GEN_MEDIA_GUID)) {
> +			struct cxl_cper_event_rec *rec = acpi_hest_get_payload(gdata);
> +
> +			cxl_cper_post_event(CXL_CPER_EVENT_GEN_MEDIA, rec);
> +		} else if (guid_equal(sec_type, &CPER_SEC_CXL_DRAM_GUID)) {
> +			struct cxl_cper_event_rec *rec = acpi_hest_get_payload(gdata);
> +
> +			cxl_cper_post_event(CXL_CPER_EVENT_DRAM, rec);
> +		} else if (guid_equal(sec_type, &CPER_SEC_CXL_MEM_MODULE_GUID)) {
> +			struct cxl_cper_event_rec *rec = acpi_hest_get_payload(gdata);
> +
> +			cxl_cper_post_event(CXL_CPER_EVENT_MEM_MODULE, rec);
>  		} else {
>  			void *err = acpi_hest_get_payload(gdata);

You pass "rec" to cxl_cper_post_event() in all these cases for later
processing in context where you can sleep to get locks. But that's
just a pointer somewhere into the "gdata" error record received from
BIOS.

What's the lifetime of that record? Can it be re-used/overwritten
before that other kernel thread gets around to looking at it?

-Tony